Note that you don’t have to do that; you can stick with the 2011Q4 (or earlier) packages you have installed now, if you don’t want to deal with software changes right now, or if you want to wait for the binary packages to become available. Upgrades/security fixes only happen for the latest quarterly release, though.

Note: don’t assume I tested this before advising you to do it, or anything like that. I mean, come on.